Thanks to the progress and development in the information technological fields, electronic products with high performance, high frequency, high operating speed and slim profile have been constantly introduced into the market. However, the heat produced by these electronic products during the high-speed operation thereof also increases to threaten the reliability and service life of the electronic products. Therefore, it has become a very important issue as how to dissipate the heat produced by the operating electronic products.
Currently, the cooling fan is one of the common heat dissipating structures for use with the heat-producing electronic products. Most of the currently available electronic products are internally equipped with a cooling fan to remove the produced heat from the electronic products, so that the electronic products can always operate within a specific operating temperature range. Due to the constantly increased demands of the electronic products for heat dissipation, the demands for enhanced air volume of the cooling fan also correspondingly increase. The most direct way to increase the cooling fan's air volume is to increase the rotational speed thereof.
A fan tends to produce vibration during the operation thereof. Such vibration increases with the rotational speed of the fan and might cause resonance of the system using the fan to thereby adversely affect the structural safety of the system. The vibration also brings noise and reduces the system stability. When two or more fans are parallelly or serially connected together in an attempt of providing increased air volume, the vibration produced by these parallelly or serially connected fans during their operation is further increased. Please refer to FIGS. 1A and 1B. A prior art fan 11 usually requires at least one additionally externally provided vibration absorbing member 12 for attaching to between the fan 11 and an electronic device, to which the fan 11 is mounted, so that the vibration absorbing member 12 absorbs the vibration produced by the fan 11 during the operation thereof. The vibration absorbing member 12 is mainly attached to one side wall of a fan frame of the fan 11 to reduce the vibration against the electronic device. In the case of using two or more parallelly or serially connected fans 11 (not shown), the externally provided vibration absorbing member 12 is also frequently provided between two adjacent fans 11 for absorbing the vibration.
Generally, the currently available slim type electronic products all have very limited internal space, which causes limitation and inconvenience in mounting the vibration absorbing members 12 to between the fan 11 and the electronic product. Thus, the cost for mounting the fan 11 and the vibration absorbing members 12 will increase while the probability of defective mounting is high to adversely affect the effect of suppressing vibration.
In brief, the prior art fan has the following disadvantages: (1) requiring increased mounting cost; (2) tending to cause the problem of poor installation thereof; and (3) providing only limited effect in suppressing the vibration produced by the fan during the operation thereof.